Serum Biomarkers in Connective Tissue Disease-Associated Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is a life-threatening complication of connective tissue diseases (CTDs) characterised by increased pulmonary arterial pressure and pulmonary vascular resistance. CTD-PAH is the result of a complex interplay among endothelial dysfunction and vascular remodelling, autoimmunity and inflammatory changes, ultimately leading to right heart dysfunction and failure. Due to the non-specific nature of the early symptoms and the lack of consensus on screening strategies-except for systemic sclerosis, with a yearly transthoracic echocardiography as recommended-CTD-PAH is often diagnosed at an advanced stage, when the pulmonary vessels are irreversibly damaged. According to the current guidelines, right heart catheterisation is the gold standard for the diagnosis of PAH; however, this technique is invasive, and may not be available in non-referral centres. Hence, there is a need for non-invasive tools to improve the early diagnosis and disease monitoring of CTD-PAH. Novel serum biomarkers may be an effective solution to this issue, as their detection is non-invasive, has a low cost and is reproducible. Our review aims to describe some of the most promising circulating biomarkers of CTD-PAH, classified according to their role in the pathophysiology of the disease.

The Challenge of Diagnosing and Managing Pulmonary Arterial Hypertension in Systemic Sclerosis with Interstitial Lung Disease.

Pulmonary hypertension (PH) in patients with Systemic Sclerosis (SSc) may stem from a variety of underlying causes, thus making a correct diagnosis and management difficult. The main challenges lie in the distinction between pulmonary arterial hypertension (PAH, group 1) and PH due to interstitial lung disease (PH-ILD, group 3) in patients with concomitant lung fibrosis ­ a very common occurrence in SSc. A consensus among experts remains elusive. Some studies have suggested that among SSc patients with PH, those with an ILD extension > 20% at high-resolution computed tomography (HRCT) should be considered as affected by PH-ILD, whereas other Authors have found that a wide proportion of these patients exhibit features of both PAH and group 3 PH-ILD. We report the case of a 46-year-old male SSc patient with a stable and extensive ILD (>20%) who developed a histologically documented pulmonary vasculopathy typical of PAH and received PAH-specific treatment as bridge to transplant. Moreover, we documented PH disease course by right heart catheterization (RHC), with and without specific vasodilator therapies, which are essential in PAH but not indicated and/or harmful in PH-ILD.

Coronary Flow Evaluation in Heart Transplant Patients Compared to Healthy Controls Documents the Superiority of Coronary Flow Velocity Reserve Companion as Diagnostic and Prognostic Tool.

Background: Distinct contributions by functional or structural alterations of coronary microcirculation in heart transplantation (HT) and their prognostic role have not been fully elucidated. We aimed to identify the mechanisms of coronary microvascular dysfunction (CMD) in HT and their prognostic implications. Methods: 134 patients, surviving at least 5 years after HT, without evidence of angiographic vasculopathy or symptoms/signs of rejection were included. 50 healthy volunteers served as controls. All underwent the assessment of rest and hyperemic coronary diastolic peak flow velocity (DPVr and DPVh) and coronary flow velocity reserve (CFVR) and its inherent companion that is based on the adjusted quadratic mean: CCFVR = √{(DPVr)2 + (DPVh)2}. Additionally, basal and hyperemic coronary microvascular resistance (BMR and HMR) were estimated. Results: Based on CFVR and DPVh, HT patients can be assigned to four endotypes: endotype 1, discordant with preserved CFVR (3.1 ± 0.4); endotype 2, concordant with preserved CFVR (3.4 ± 0.5); endotype 3, concordant with impaired CFVR (1.8 ± 0.3) and endotype 4, discordant with impaired CFVR (2.0 ± 0.2). Intriguingly, endotype 1 showed lower DPVr (p < 0.0001) and lower DPVh (p < 0.0001) than controls with lower CFVR (p < 0.0001) and lower CCFVR (p < 0.0001) than controls. Moreover, both BMR and HMR were higher in endotype 1 than in controls (p = 0.001 and p < 0.0001, respectively), suggesting structural microvascular remodeling. Conversely, endotype 2 was comparable to controls. A 13/32 (41%) patients in endotype 1 died in a follow up of 28 years and mortality rate was comparable to endotype 3 (14/31, 45%). However, CCFVR was < 80 cm/s in all 13 deaths of endotype 1 (characterized by preserved CFVR). At multivariable analysis, CMD, DPVh < 75 cm/s and CCFVR < 80 cm/s were independent predictors of mortality. The inclusion of CCFVR < 80 cm/s to models with clinical indicators of mortality better predicted survival, compared to only adding CMD or DPVh < 75 cm/s (p < 0.0001 and p = 0.03, respectively). Conclusion: A normal CFVR could hide detection of microvasculopathy with high flow resistance and low flow velocities at rest. This microvasculopathy seems to be secondary to factors unrelated to HT (less rejections and more often diabetes). The combined use of CFVR and CCFVR provides more complete clinical and prognostic information on coronary microvasculopathy in HT.

The paradox of pulmonary arterial hypertension in Italy in the COVID-19 era: is risk of disease progression around the corner?

OBJECTIVE: The coronavirus disease 2019 (COVID-19) outbreak has led to significant restrictions on routine medical care. We conducted a multicentre nationwide survey of patients with pulmonary arterial hypertension (PAH) to determine the consequences of governance measures on PAH management and risk of poor outcome in patients with COVID-19. MATERIALS AND METHODS: The present study, which included 25 Italian centres, considered demographic data, the number of in-person visits, 6-min walk and echocardiographic test results, brain natriuretic peptide/N-terminal pro-brain natriuretic peptide test results, World Health Organization functional class assessment, presence of elective and non-elective hospitalisation, need for treatment escalation/initiation, newly diagnosed PAH, incidence of COVID-19 and mortality rates. Data were collected, double-checked and tracked by institutional records between March 1 and May 1, 2020, to coincide with the first peak of COVID-19 and compared with the same time period in 2019. RESULTS: Among 1922 PAH patients, the incidences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19 were 1.0% and 0.46%, respectively, with the latter comparable to that in the overall Italian population (0.34%) but associated with 100% mortality. Less systematic activities were converted into more effective remote interfacing between clinicians and PAH patients, resulting in lower rates of hospitalisation (1.2% versus 1.9%) and related death (0.3% versus 0.5%) compared with 2019 (p<0.001). A high level of attention is needed to avoid the potential risk of disease progression related to less aggressive escalation of treatment and the reduction in new PAH diagnoses compared with 2019. CONCLUSION: A cohesive partnership between healthcare providers and regional public health officials is needed to prioritise PAH patients for remote monitoring by dedicated tools.

Multiparametric analysis of coronary flow in psoriasis using a coronary flow reserve companion.

BACKGROUND: Coronary microvascular dysfunction (CMD) is usually evaluated measuring coronary flow velocity reserve (CFVR). A more comprehensive analysis of CFVR including additional consideration of the associated logical companion-CFVR, where hyperemic diastolic coronary flow velocity may act as surrogate, was applied in this study to elucidate the mechanism of CMD in psoriasis. METHODS AND RESULTS: Coronary flow velocity reserve was analysed using transthoracic echocardiographs of 127 psoriasis patients (age 36 ± 8 years; 104 males) and of 52 sex- and age-matched healthy controls. CFVR determination was repeated in the patient subgroup (n = 78) receiving anti-inflammatory therapy. Baseline and hyperemic microvascular resistance (MR) were calculated. CMD was defined as CFVR ≤ 2.5. Four endotypes of CMD were identified referring to concordant or discordant impairments of hyperemic flow or CFVR. We evaluated the companion-CFVR, as derived from the quadratic mean of hyperemic and diastolic flow velocity at rest. Coronary flow parameters, including CFVR (p = 0.01), were different among the two endotypes having CFVR > 2.5. Specifically, all 11 (14%) patients with CFVR deterioration despite therapy, belonged to endotype 1, and had higher baseline and hyperemic MR (p < 0.0001, both). Interestingly, while CFVR was comparable in patients with worsened versus those with improved CFVR, the companion-CFVR could discriminate by being lower in patients with worsened CFVR (p = 0.01). CONCLUSIONS: The reduced CFVR in psoriasis is driven by decreased companion-CFVR, combined with increased hyperemic MR. Adoption of the mandatory companion-CFVR enables a personalized characterization superior to that achieved by exclusive consideration of CFVR.

Characteristics and hospital course of patients admitted for acute cardiovascular diseases during the coronavirus disease-19 outbreak.

INTRODUCTION: During the coronavirus disease-19 (COVID-19) outbreak in spring 2020, people may have been reluctant to seek medical care fearing infection. We aimed to assess the number, characteristics and in-hospital course of patients admitted for acute cardiovascular diseases during the COVID-19 outbreak. METHODS: We enrolled all consecutive patients admitted urgently for acute myocardial infarction, heart failure or arrhythmias from 1 March to 31 May 2020 (outbreak period) and 2019 (control period). We evaluated the time from symptoms onset to presentation, clinical conditions at admission, length of hospitalization, in-hospital medical procedures and outcome. The combined primary end point included in-hospital death for cardiovascular causes, urgent heart transplant or discharge with a ventricular assist device. RESULTS: A similar number of admissions were observed in 2020 (N = 210) compared with 2019 (N = 207). Baseline characteristics of patients were also similar. In 2020, a significantly higher number of patients presented more than 6 h after symptoms onset (57 versus 38%, P < 0.001) and with signs of heart failure (33 versus 20%, P = 0.018), required urgent surgery (13 versus 5%, P = 0.004) and ventilatory support (26 versus 13%, P < 0.001). Hospitalization duration was longer in 2020 (median 10 versus 8 days, P = 0.03). The primary end point was met by 19 (9.0%) patients in 2020 versus 10 (4.8%) in 2019 (P = 0.09). CONCLUSION: Despite the similar number and types of unplanned admissions for acute cardiac conditions during the 2020 COVID-19 outbreak compared with the same period in 2019, we observed a higher number of patients presenting late after symptoms onset as well as longer and more complicated clinical courses.

New insights to the potential mechanisms driving coronary flow reserve impairment in Cushing's syndrome: A pilot noninvasive study by transthoracic Doppler echocardiography.

BACKGROUND: The contribution of functional and/or structural remodeling to reduced coronary flow velocity reserve (CFVR), reflecting impaired coronary microcirculation in Cushing's syndrome (CS), has not been clearly elucidated. We aimed to identify the potential mechanisms of coronary microvascular impairment in CS. METHODS: We studied 15 CS patients (11 female, age 50 ±â€¯9 years) without clinical evidence of cardiovascular disease. Coronary flow velocity in the left anterior descending coronary artery was measured by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. Average peak flow velocities, CFVR, and microvascular resistance in baseline (BMR) and hyperemic conditions (HMR) were assessed. CFVR ≤2.5 was considered a marker of microvascular disease (CMD). Diastolic function (E/e'), global longitudinal strain (GLS) and fractional pulse pressure (fPP), an index of arterial stiffness, were also assessed. RESULTS: CMD was present in 5 patients (33.3%). CMD was primarily driven by increased baseline peak flow velocity (29 ±â€¯12 versus 19.6 ±â€¯4.2 cm/s, p = .03) in the presence of decreased BMR (3.62 ±â€¯0.6 versus 5.46 ±â€¯1.4 mm Hg·s/cm, p = .03). Moreover, urinary cortisol and E/e' were higher (p = .001 and p = .001, respectively) and GLS was lower (p = .009) in patients with CMD. fPP was higher in patients with CMD (p = .01). Urinary cortisol correlated to CFVR (p = .008), E/e' (p < .0001) and GLS (p < .0001). fPP directly correlated to average peak flow velocities at rest (p = .01) and inversely to BMR (p = .03). CONCLUSIONS: Functional microvascular regulatory impairment seems to be the potential mechanism of CMD in CS. CMD seems to be related to decreased myocardial contractility and diastolic dysfunction associated with cortisol excess.

Long-term prognostic value of coronary flow reserve in psoriasis patients.

BACKGROUND AND AIMS: Psoriasis affects more than 3% of the general population and is associated with an increased risk of premature cardiovascular events and death. We assessed the prognostic role of coronary flow reserve (CFR) as a marker of coronary microvascular function in psoriasis patients asymptomatic for cardiovascular disease. METHODS: We retrospectively analyzed 153 prospectively collected patients affected by psoriasis (123 male; age 36 ±â€¯8 years) without cardiovascular disease. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. CFR was the ratio of hyperemic to resting diastolic flow velocity. CFR ≤2.5 was the cut off to define the presence of coronary microvascular dysfunction (CMD). RESULTS: CMD was present in 23 patients (15%). Multivariable logistic regression analysis showed that CMD was associated with severe psoriasis (OR 3.1, p = 0.03), psoriatic arthritis (OR 2.9, p = 0.03), hypertension (OR 4.1, p = 0.009), and time elapsing since psoriasis diagnosis >6 years (OR 1.9, p = 0.03). Patients with CFR ≤2.5 had a lower survival free from events (p < 0.0001). CONCLUSIONS: In psoriasis patients, CFR may be a reliable prognostic marker for cardiovascular event-free survival and may help identify patients at higher risk of developing cardiovascular complications. Whether novel biologic therapies able to reduce skin disease will improve CMD and prognosis in these patients needs to be further studied, prospectively.

Pulmonary arterial hypertension in connective tissue disorders: Pathophysiology and treatment.

IMPACT STATEMENT: Our article focuses on the pathogenesis and treatment of CTD-PAH. In the latest ESC/ESR guidelines for PAH, the authors underline that although CTD-PAH should follow the same treatment protocol as idiopathic PAH, the therapeutic approach is more complex and difficult in the former. This review throws light on several peculiar aspects of CTD-PAH and the latest findings in the pathogenesis, namely, the role of inflammation in the maladaptive right ventricle remodeling in SSc-PAH where immunosuppressants are classically believed to be ineffective. Furthermore, we discuss the major critical points in the therapy of CTD-PAH which is one of the strengths of our article. To the best of our knowledge, there are no other reviews that exclusively focus on the pathogenesis and treatment of CTD-PAH patients, with an emphasis on the more critical issues. Thus, it is our contention that our work would be of interest to the readers.

Coronary flow reserve in patients with primary biliary cholangitis.

BACKGROUND: It is still not clear whether primary biliary cholangitis (PBC) is associated with abnormalities of the cardiovascular system. We aimed to assess the relationship between PBC and coronary flow reserve (CFR). METHODS: Our inclusion criterion was a diagnosis of PBC with no clinical evidence of heart disease or metabolic syndrome. Coronary flow velocity in the left anterior descending coronary artery was measured using transthoracic Doppler echocardiography at rest (DFVr), and during adenosine infusion (DFVh). The corrected CFR (cCFR) was defined as the ratio of DFVh to DFVr corrected for cardiac workload (cDFVr). Microvascular resistance was also assessed in baseline (BMR) and hyperemic conditions (HMR). RESULTS: 37 PBC patients and 37 sex- and age-matched controls were considered. The cCFR was significantly lower in PBC patients (2.8 ±â€¯0.7 vs. 3.7 ±â€¯0.7, p < 0.0001), and abnormal (≤2.5) in 13 (35%) of them, but in none of the controls (p < 0.0001). The cDFVr was higher in patients with abnormal cCFR (29.0 ±â€¯6.0 vs. 20.4 ±â€¯4.5 cm/sec, p < 0.0001). The CFR and cCFR did not correlate with any characteristics of PBC, comorbidities or Framingham risk scores. The BMR and HMR correlated with time since PBC diagnosis and duration of symptoms. CONCLUSION: The CFR is reduced in PBC, apparently due to mechanisms correlating with the time since diagnosis. In particular, the higher cDFVr with a lower basal resistance in patients with cCFR ≤ 2.5 suggests a compensatory mechanism against any cardiomyocyte bioenergetics impairment.

Link between von Willebrand factor multimers, relapses and coronary microcirculation in patients with thrombotic thrombocytopenic purpura in remission.

INTRODUCTION: ADAMTS13 deficiency results in unusually large von Willebrand factor (ULVWF) multimers in the circulation and a higher risk of microthrombi due to high shear stress. In patients treated for acquired thrombotic thrombocytopenic purpura (TTP), a persistently severe ADAMTS13 deficiency (<10%) in remission is associated with more relapses. A reduced plasma ADAMTS13 activity and increased VWF levels are associated with a higher risk of myocardial infarction. Assessing coronary flow reserve (CFR) enables a better cardiovascular risk stratification: a lower CFR correlates inversely with cardiovascular risk. The aim of the study was to establish whether patients with TTP in remission have an impaired coronary microcirculation, in terms of a lower CFR, and whether there is any correlation between ADAMTS13 activity, the presence of ULVWF multimers, and the occurrence of relapses. METHODS: The clinical information and hemostatic parameters of 24 patients with TTP in remission managed at our center were analyzed. The CFR was assessed in a subgroup of the TTP patients and compared with a control group consisting of 50 healthy volunteers. RESULTS: The CFR was statistically lower in patients in remission of TTP than in controls, but there were no differences between TTP patients with normal and lower CFR. The occurrence of relapses correlated with the presence of ULVWF multimers and with a residual ADAMTS13 activity. CONCLUSIONS: When compared with healthy controls, TTP patients in remission have an impaired coronary microcirculation and the occurrence of relapses in the former reveal the presence of ULVWF multimers.

Nailfold avascular score and coronary microvascular dysfunction in systemic sclerosis: A newsworthy association.

BACKGROUND AND AIMS: We aimed to assess the relationship between nailfold videocapillaroscopy (NVC) abnormalities and coronary flow reserve (CFR), a marker of coronary microvascular dysfunction (CMD) in patients with systemic sclerosis (SSc). METHODS: We studied 39 SSc patients (33 females, mean ±â€¯SD age 54 ±â€¯12 years, median disease duration 11 years, range 6-22) and 22 controls (matched for age and sex) without any evidence of cardiovascular disease. Clinical assessment was performed by modified Rodnan skin score (mRss) and EUSTAR score. Coronary flow velocities in the left anterior descending coronary artery were measured by transthoracic echocardiography. Average peak flow velocities, CFR and microvascular resistance at baseline (BMR) and in hyperaemic (HMR) condition were assessed. CFR ≤2.5 was considered marker of CMD. Six NVC-abnormalities were evaluated by a semi quantitative scoring system: enlarged and giant capillaries (diameter > 20 µm and >50 µm, respectively), hemorrhages, disarray, capillary ramifications and loss of capillaries (avascular score). Statistic was performed using SPSS. RESULTS: CFR was lower in SSc patients than in controls (2.6 ±â€¯0.5 vs 3.3 ±â€¯0.5). CMD was detected in 24 patients (61.5%) vs 0 controls (p < .0001). CFR was inversely correlated with NVC-avascular score (rho =-0.750, p < .0001). Avascular and capillary ramifications scores (p = .001 and p = .03, respectively), mRss (p = .003) and EUSTAR score (p = .01) were higher in patients with CMD than in those without. At multivariable analysis, avascular score was independently associated with CMD (p = .01). HMR was directly correlated with avascular score (rho = 0.416, p = .008). CONCLUSIONS: In our SSc patients NVC-avascular score was associated with CMD which seems to be the result of a structural microvascular remodeling.

Coronary microvascular dysfunction may be related to IGF-1 in acromegalic patients and can be restored by therapy.

BACKGROUND AND AIMS: Acromegaly increases the risk of cardiovascular mortality. Data on the cardiovascular risk in asymptomatic acromegaly are limited. In particular, data on coronary microvascular abnormalities are lacking. We assessed coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic acromegaly. METHODS: We studied 40 acromegalic patients (23 male, age 52 ±â€¯11 years) without clinical evidence of cardiovascular disease, and 40 control subjects matched for age and sex. Coronary flow velocity in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. CFR was the ratio of hyperaemic to resting diastolic flow velocity. RESULTS: CFR was lower in patients than in controls (2.9 ±â€¯0.8 vs. 3.7 ±â€¯0.6, p < 0.0001) and was abnormal (≤2.5) in 13 patients (32.5%) compared with any control subjects (0%) (p < 0.0001). CFR was inversely related to insulin-like growth factor 1 (IGF-1) levels (r = -0.5, p < 0.004). In patients with CFR≤2.5, IGF-1 was higher (756 [381-898] µg/l versus 246 [186-484] µg/l, p < 0.007) whereas growth hormone (GH) levels were similar (6.3 [2.8-13.7] µg/l versus 5 [2.8-8.9] µg/l, p = 0.8). In multivariable linear regression analysis, IGF-1 was independently associated with CFR (p < 0.0001). In multiple logistic regression analysis, IGF-1 independently increased the probability of CFR≤2.5 (p = 0.009). In four patients with active disease (all with CFR<2.5), treatment with somatostatin analogues normalized CFR. However the other four patients with active disease were not responder. CONCLUSIONS: Acromegalic patients have coronary microvascular dysfunction that may be restored by therapy with somatostatin analogues. IGF-1 independently correlates with the coronary microvascular impairment, suggesting the pivotal role of this hormone in explaining the increased cardiovascular risk in acromegaly.

Treatment with tumor necrosis factor inhibitors restores coronary microvascular function in young patients with severe psoriasis.

BACKGROUND AND AIMS: In patients with psoriasis, the chronic exposure to systemic inflammation can result in coronary microvascular dysfunction (CMD). In this self-controlled, prospective pilot study, we investigated whether a long-term treatment with TNF-α inhibitors effective against skin symptoms also improves coronary flow reserve in psoriasis patients (CFR). METHODS: We prospectively studied 37 consecutive psoriasis patients (31 male; age, 37.7 ± 8.5 years) without cardiovascular disease, before and after anti-TNF-α treatment. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest and during adenosine infusion. CFR was the ratio of hyperemic to resting diastolic flow velocity. A CFR≤2.5 was considered a marker of CMD. Psoriasis was assessed by Psoriasis Area and Severity Index (PASI). High sensitive C-reactive protein (hs-CRP) and serum TNF-α were assessed. RESULTS: Overall, CFR increased from 2.2 ± 0.7 to 3.02 ± 0.8 (p < 0.0001) after TNF-α inhibitors therapy. In patients with CMD, CFR increased from 1.88 ± 0.3 to 2.74 ± 0.5 (p < 0.0001). In patients with normal CFR, CFR increased from 3.0 ± 0.5 to 3.7 ± 0.9 (p = 0.08). CFR improvement after TNF-α inhibitors treatment was correlated with hs-CRP and TNF-α reduction (p = 0.004 and p = 0.02, respectively), but not with change in PASI (p = 0.5). CONCLUSIONS: The present study demonstrates that TNF-α inhibitors treatment ameliorates CMD in patients with established psoriasis not responding to long-term conventional therapy. These findings suggest that a therapy specifically targeted against inflammation is able to positively affect coronary microvascular function.

Coronary microvascular dysfunction due to essential thrombocythemia and policythemia vera: the missing piece in the puzzle of their increased cardiovascular risk?

Myeloproliferative neoplasms are most commonly associated with venous thrombosis. Up to 60% of patients experience a thrombotic event in their lifetimes, including stroke or myocardial infarction. It is unclear whether pathogenetic factors linking essential thrombocythemia (ET) and polycythemia vera (PV) to thrombotic complications do play a role in the risk of coronary artery disease (CAD). We aimed to assess coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic patients with ET and PV. Fifty-two patients with ET (M/F 13/39, age 61 ± 7 years) and 22 patients with PV (M/F 13/9, age 60.4 ± 13 years) without clinical evidence of heart disease, and 50 controls matched for age and gender were studied. None had CAD. All control subjects were asymptomatic with no history of heart disease. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. In patients with ET and PV, CFR was lower than in controls (2.9 ± 0.94 and 2.2 ± 0.7 vs. 3.8 ± 0.7, P < 0.004 and P < 0.0001 respectively). The prevalence of CFR ≤ 2.5 was higher in patients with ET (20 cases, 38.5%) and PV (15 cases, 68.2%) compared with controls (4.1%) (P < 0.0001). Severe CFR (CFR < 2) impairment was found in eight patients with ET (15.4%), in nine patients with PV (40.9%), and in none of control subjects. The mutation of JAK2 gene was associated with abnormal CFR. Asymptomatic patients with ET and PV have coronary microvascular dysfunction in the absence of clinical conditions suggesting CAD.

Coronary microvascular function in patients with Cushing's syndrome.

The aim of the study was to evaluate patients with Cushing's syndrome the coronary flow reserve (CFR), an index of coronary microvascular function. Fifteen newly diagnosed patients with Cushing's syndrome (1 male/14 females; mean age 45 ± 11 years), were selected for having no clinical evidence of ischemic heart disease. Twelve patients had pituitary-dependent Cushing's disease and three had an adrenal adenoma. Fifteen subjects matched for age, sex, and major cardiovascular risk factors were used as controls. Coronary flow velocity in the left anterior descending coronary artery was investigated by transthoracic Doppler echocardiography at rest and during adenosine infusion. CFR was obtained as the ratio hyperemic/resting diastolic flow velocity. A reduced coronary reserve (hyperemic/resting ratio ≤ 2.5) was found in 5/15 Cushing patients and 4/15 controls. In all patients with abnormal CFR, epicardial coronary stenosis was excluded by multi-slice computed tomographic coronary angiography. CFR was inversely related to urinary cortisol in patients with endogenous hypercortisolism (Spearman's rho = -0.57, P = 0.03), while no correlation was found in controls. Coronary microvascular function, as assessed by CFR, is pathologically reduced in a considerable number of patients with Cushing's syndrome without clinical symptoms of ischemic heart disease and in the absence of epicardial coronary artery lesions, as well as in controls matched for cardiovascular risk factors. The presence of comorbidities can explain this early coronary abnormality in both patients and controls. Whether urinary cortisol may be a predictor of coronary microvascular function in the setting of patients with Cushing's syndrome, needs further investigation.

Coronary microvascular dysfunction induced by primary hyperparathyroidism is restored after parathyroidectomy.

BACKGROUND: Symptomatic primary hyperparathyroidism (PHPT) is associated with increased cardiovascular mortality. However, data on the association between asymptomatic PHPT and cardiovascular risk are lacking. We assessed coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic PHPT of recent onset. METHODS AND RESULTS: We studied 100 PHPT patients (80 women; age, 58±12 years) without cardiovascular disease and 50 control subjects matched for age and sex. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. CFR was the ratio of hyperemic to resting diastolic flow velocity. CFR was lower in PHPT patients than in control subjects (3.0±0.8 versus 3.8±0.7; P<0.0001) and was abnormal (≤2.5) in 27 patients (27%) compared with control subjects (4%; P=0.0008). CFR was inversely related to parathyroid hormone (PTH) levels (r=-0.3, P<0.004). In patients with CFR ≤2.5, PTH was higher (26.4 pmol/L [quartiles 1 and 3, 16 and 37 pmol/L] versus 18 [13-25] pmol/L; P<0.007), whereas calcium levels were similar (2.9±0.1 versus 2.8±0.3 mmol/L; P=0.2). In multivariable linear regression analysis, PTH, age, and heart rate were the only factors associated with CFR (P=0.04, P=0.01, and P=0.006, respectively). In multiple logistic regression analysis, only PTH increased the probability of CFR ≤2.5 (P=0.03). In all PHPT patients with CFR ≤2.5, parathyroidectomy normalized CFR (3.3±0.7 versus 2.1±0.5; P<0.0001). CONCLUSIONS: PHPT patients have coronary microvascular dysfunction that is completely restored after parathyroidectomy. PTH independently correlates with the coronary microvascular impairment, suggesting a crucial role of the hormone in explaining the increased cardiovascular risk in PHPT.

Recent developments on coronary microvasculopathy after heart transplantation: a new target in the therapy of cardiac allograft vasculopathy.

Heart transplantation (HTx) is the treatment of choice for patients with refractory end-stage heart diseases. Although the procedure is considered effective in extending and improving quality of life, the onset of cardiac allograft vasculopathy (CAV) continues to limit the long-term success of HTx. Emerging data indicate that the endothelium plays a significant role in the onset, progression and complication of this multifactorial disease, with both immunologic and nonimmunologic risk factors contributing to its development. Improving our understanding of the integral role of the coronary microcirculation in CAV is of crucial clinical interest since it could provide further insights into the related pathophysiological mechanisms and possible new strategies for CAV prevention and therapy. Assessment of coronary microvasculopathy has been shown to be of predictive value after HTx. Predominant allograft microvascular dysfunction is detectable in 15-20% of patients after HTx. Very recently, stenotic microvasculopathy (detected in biopsy samples) has been characterized as a prognostic factor for long-term survival after HTx. The ability to detect and distinguish changes in epicardial and microvascular function may aid in identifying modifiable factors that lead to CAV. Improved immunosuppressive drugs, including mycophenolate mofetil and proliferation signal inhibitors, as well as statins (in part via immunomodulation), may have a beneficial effect on coronary microcirculation after HTx, although there is still a need to confirm the impact of vasodilators in improving the prognosis of HTx patients. We review the role of coronary microvasculopathy in HTx, its prevention and new potential pharmacological interventions.